Automatic hydraulic centering device



March 3, 1970 e. w. COPE AUTOMATIC HYDRAULIC CENTERING DEVICE 2Sheets-Sheet 1 Filed Jan. 7, 1965 In v e n t o r Geoffrey W. C o p 6 hisAttorney March 3, 1970 e. w. cops 3,498,475

AUTOMATIC HYDRAULIC CENTERING DEVICE Filed Jan. 7 1966 2 Sheets-Sheet 2v 20 20 'Il/IIIIIIIIII/Ili/IIIIIIIII11/ FIG. 3

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In v e n to r:

Geoffrey W. Cop e his Attorney United States Patent US. Cl. 213- 11Claims ABSTRACT on THE DISCLOSURE A device for automatically centering ahead of an uncoupled horizontally swingable railway coupler onunderlying track, having hydraulically connected master and slavehydraulic units respectively connected to an adjoining truck away fromthe trucks pivot and acting on the coupler forwardly of the pivot aboutwhich the coupler swings horizontally for horizontally swinging thecoupler when uncoupled in response to horizonizontal angling of thetruck and yieldable means disposed between the coupler and truck andoperative when the coupler is coupled for enabling the coupler to swinghorizontally independently of the horizontal angling of the truck.

This invention relates to automatic centering devices for railway carcouplers.

Automatic couplers, such as now used on railroads and rapid transitlines, are designed to couple automatically with a mating coupler butwill only so couple if impacted by the mating coupler within thegathering range of their heads. To follow track curvatures when coupled,a conpler must be capable of swinging horizontally, with the extent ofthe swing determined by the length of the overhang of the car beyond itstrucks and the minimum radius curve the car must negotiate. A couplercan be adapted to couple on straight track by centering it on thecenterline of the car and there are a number of devices suitable for thepurpose. However, to be coupleable on both straight and curved track, anuncoupled coupler must have its head centered not on the centerline ofthe car but on that of the underlying track. Approximate centering,within the gathering range of the heads of the couplers being coupled,will sufi'ice, and it is in this sense that the term centering is hereused. Unless the couplers intended to be coupled are so centered, notonly can they not couple but the coupling impact, instead of being takenthrough the cars cushioning devices, is taken directly by their ends anddamage is almost inevitable. The problem is particularly acute incoupling long freight cars and subway cars.

The primary object of the present invention is to provide a hydrauliccentering device for automatically centering an uncoupled coupler onunderlying track in position to couple with a mating coupler.

Another object of the invention is to provide an automatic hydrauliccoupler centering device which derives its centering action from thehorizontal angling of the adjoining truck relative to the car body andtranslates that angling into horizontal angling or swinging of thecoupler in the same direction and to the extend necessary to center itshead on the underlying track.

An additional object of the invention is to provide an automatichydraulic coupler centering device which, While exerting a centeringaction on the coupler whether it is coupled or uncoupled, permits acoupled coupler to deviate from centered position to accommodate specialconditions, such as those experienced on tangent points and reversecurves.

FIGURE 1 is a somewhat diagrammatic plan view of an end portion of asubway car fitted with an embodi- 3,498,475 Patented Mar. 3, 1970 mentof the automatic hydraulic coupler centering device of the presentinvention;

FIGURE 2 is a side elevational view of the structure of FIGURE 1;

FIGURE 3 is a vertical sectional view on an enlarged scale taken alongline 3-3 of FIGURE 2;

FIGURE 4 is a partial plan view of the car end portion of FIGURE 1showing a second embodiment of the centering device of the presentinvention;

FIGURE 5 is a partial plan view of the car end portion of FIGURE 1showing a third embodiment of the centering device of the presentinvention; and

FIGURE 6 is a diagrammatic plan view on a reduced scale of the structureof FIGURE 1.

Referring now in detail to the drawings in which like referencecharacters designate like parts, the improved automatic centering deviceof this invention, While applicable generally to railway car couplersand far more useful than devices for centering a coupler on a carscenterline, is of particular benefit on subway or rapid transit cars andpiggyback or other long freight cars having long overhangs. Equallyapplicable whether a car has a fixed or a cushioned underframe, theimproved centering device has been applied for purposes of illustrationto a coupler of the type generally used on subway cars.

As typical of couplers with which subway cars are equipped, theillustrated coupler 1 is the automatic hook type coupled disclosed indetail in Cope Patent No. 3,181,708, issued May 4, 1965. The coupler 1is connected for relative horizontal swinging, angling or pivoting tothe cars body, indicated at 2, but, unlike a standard freight carcoupler, is so connected through a drawbar 3, which, insofar as thisinvention is concerned, forms a rearward extension of the couplers shank4. A head 5 of the coupler, integral with its shank 4, contains apivoted hook 6 which projects forwardly through the heads flat front orbufling face 7 lying on the couplers coupling line. For enabling thecoupler automatically to connect the cars electric and air service lines(not shown) to those of another car, as the cars are mechanicallyconnected, the couplermounts on its head 5 suitable electric and fluidcouplings 8 and 9, respectively.

The shank 4 of the coupler 1 is connected for vertical swinging orpivoting to a yoke 10 which slides longitudinally in the drawbar 3 andis cushioned in its longitudinal movements under bufiing and draftforces on the coupler by a rubber or other suitable cushioning unitmounted in the drawbar. At the rear the drawbar 3 is connected by avertical drawbar pin 12 to an anchor bracket or anchorage 13 fixed tothe underside or fixed underframe 14 of the car body 2. Supported at therear and angleable, swingable or pivotable horizontally on the anchorbracket 13 about a vertical pivot or axis P coincident with the axis ofthe pivot pin 12, the drawbar 3 is slidably supported at the front on aradial carrier bar 15 fixed to and suspended from the car body 2.

Rearwardly or inwardly of the anchor bracket 13, the car body 2 ismounted on one of a pair of trucks, only the bolster 16 of which isshown. As usual, the adjoining truck is connected to the car body forrelative horizontal angling, swinging or pivoting through the bolster 16by a vertical kingpin 17, the axis of which is the trucks pivotal axisor vertical pivot P When a car is on a curve, its trucks are angledhorizontally relative to its body. At that time, the truck pivot P is onthe centerline of the track and the centerline of the bolster 16 issubstantially on a radius of the curve passing through the pivot. It isthis angling of the truck as it follows the curvature of the track thatis here used to center the head 5 of the coupler 1 on the part of thetrack underlying it. Deriving its centering action from the angling ofthe adjoining truck relative to the car body, the im proved centeringdevice, designated as 18, operatively connects the coupler 1 to theadjoining truck for hydraulically translating horizontal angling of thetruck relative to the car body into horizontal angling of the coupler,such that the latters head 5 is centered on underlying track.

The hydraulic centering device 18 is comprised of one or more master ordrive cylinder units 19, each mechanically connected to the truck at adistance from the truck pivot P and hydraulically connected to a slaveor driven cylinder unit 20 for transmission of force therebetween by thedisplacement of oil or other suitable liquid. In turn, each slave unit20 is mechanically connected to the coupler 1 forwardly of its and thedrawbars vertical pivot P for applying to the coupler the forcetransmitted to the slave unit from the related or associated master unit19. Each master unit 19 conveniently is connected to the bolster 16 orother cross member of the truck and mounted forwardly thereof on thefixed underframe 14 of the car body 2, for relative movement of itscylinder 21 and piston 22 in substantial correspondence with thehorizontal angling of the truck relative to the car body.Liquid-connected to the related master unit 19 through suitable tub ing23, each slave unit 20 is mounted on the underframe 14 and connectedeither directly to the coupler or to a member, such as the drawbar 3,which swings horizontally in unison with the coupler, for swinging orangling the coupler horizontally in substantial correspondence with therelative or longitudinal axial movement of the slave units cylinder 24and piston 25.

In the first embodiment in FIGURES 1-3, there are two master cylinderunits 19 mounted equidistantly on opposite sides of the centerline ofthe car and disposed or extending substantially parallel to thatcenterline in the neutral or at rest position in which the truck is atzero angling, with the longitudinal centerlines of the car and thebolster 16 normal or perpendicular to each other. Thus oifset laterallyrelative to the truck pivot P each of the preferred master units 19, inorder to be both telescoped or compressed and elongated as the bolsterturns or angles horizontally in one direction or the other from neutralposition, must itself be capable of swinging or angling to a degreedependent upon its lateral offset. For this purpose each master unit ispivotally connected to both the bolster 16 and the car body 2, as byhaving the opposite ends of its piston rod 26 and cylinder 21 clevisedfor pivotal connection of one to a bracket 27 on or fixed to the frontor confronting side of the bolster and the other to a mounting bracket28 attached to the underframe 14 of the car body 2, the rod here beingconnected to the bolster bracket and the cylinder to the car bodybracket. To compensate for manufacturing tolerances, the connection 29between each car body bracket 28 and the related master cylinder unit 19preferably is adjustable so that the bracket within limits can beshifted either longitudinally or laterally of the body. To accommodatethe angling of each master unit 19, the tubing 23 connecting it to therelated slave unit 20 can be either flexible tubing or in the mainrigid, with a section 30 of flexible, preferably armored, hose in itsend portion adjoining the master unit.

As opposed to the master units 19, the slave units 20 are disposed ordirected laterally of the car and normal or perpendicular to itslongitudial centerline. Each slave unit 20 is connected at one end to abracket 31 fixed to the underframe 14 and at the other to the coupler 1,the preference being to connect its cylinder 24 to the bracket and therod 32 of its piston 25 to the coupler. Rather than connect themindividually to the coupler 1, the slave rods 32 preferably areconnected to and act on the coupler through a centering yoke 33receiving and having arms 34 laterally embracing or straddling andconfronting opposite sides either of the shank 4 or, as illustrated, ofhearing plates or pads 35 fixed to and providing flat bearing surfaceson the sides of the drawbar 3, which here forms the shanks rearwardextension. Disposed laterally of the car body 2, the centering yoke 33is open longitudinally thereof to pass the drawbar 3 and also openseither upwardly or downwardly, depending on whether, as convenient, itis applied from below or, as illustrated, above to the drawbar. Insteadof directly engaging the bearing plates 35 at the sides of the drawbar3, the yoke arms 34 embracing those sides preferably are lined with pads36 of Teflon or like Wear-resistant, lubricious material, the innerfaces 37 of which are arcuately convex and spaced slightly more than theembraced width of the drawbar to accommodate the relative anglingtherebetwee'n.

In this first embodiment in which the master and slave units 19 and 20are all single-acting units, angling of the bolster 16 out of neutralposition as the car negotiates curved track, will compress or telescopethe master unit at one side and correspondingly expand or elongate theother master unit. Connected on its liquid side to the liquid side ofthe related slave cylinder 20 by the tubing 23, the compressed masterunit will displace liquid to the slave unit and, by expanding orelongating the latter and projecting its piston rod 32, shift thecentering yoke 33 toward the opposite side of the car and, therethrough,swing or angle the coupler 1 toward that side. Since the piston rod 32of the other slave unit 20 is also connected to the yoke 33, it will becompressed or telescoped by the shifting of the yoke by the first unitand positively displace the excess liquid to the related master unit 19.Subsequent turning or swinging of the bolster 16 back to neutralposition, as the car reaches straight track, will re verse this actionand return the coupler 1 to a position in which it is centered on thecar body 2 as well as on the underlying track.

The above-described centering action serves to center an uncoupledcoupler on either curved or straight underlying track in position tocouple with a mating coupler and in most cases would reflect and notinterfere with the angling of the coupler when coupled. However, underspecial conditions, as on tangents and reverse curves, a coupled couplermust deviate from the track-centered position in which the centeringdevice 18 would hold it. Accordingly, it is necessary that there be someyieldability in the centering device to accommodate such specialconditions of the coupler 1, when coupled, without detriment to thecentering of the coupler, when uncoupled, on underlying track. In thefirst embodiment, the

necessary yieldability is obtained conveniently by making the centeringyoke 33 I-l-shaped with side webs 38 connecting extensions 39 of thearms 34 embracing or straddling the drawbar 3, the arm extensions 39being apertured to fit over and slidably receive the piston rods 32 ofthe slave units 20. The rods 32 have their ends connected between thearm extensions 39 by a connecting rod 40 of smaller diameter screwed orotherwise connected at its ends thereto and slidably mounting a pair ofbushings 41. A relief spring 42 mounted on the sleeve 40 and interposedbetween the bushings 41, is of a strength to yield to and be compressedby the deviational forces acting under special track conditions on acoupled coupler, but not by the lesser forces initiated at the truck tocenter the coupler. With the relief spring 42 of such strength, thecentering yoke 33 will normally be connected for movement in unison withthe rods 32 of the slave cylinders 20 and can move axially relative tothe rods whenever required to meet deviational conditions.

The second form of the centering device shown in FIGURE 4 is identicalwith the first except in its provision for yieldability to meet specialor deviational conditions. In this second form the common relief spring42 of the first has its function performed by a pair of accumulators 43,one connected in the line or tubing 23 between each master unit 19 andits slave unit 20. The centering yoke 33 and the slave piston rods 32being fixed against relative movement in this form, the ac cumulators43, to perform their intended function, must in effect be by-passedexcept under special or deviational conditions and then be adapted toreceive the excess liquid occasioned by the deviation in the line at theside to ward which the coupler is swung. Suitably, the accumulators 43can be of the type having a chamber 44 connected to the liquid line 23and partly filled with a compressed gas either immiscible with theliquid or, as indicated, separated therefrom by a diaphragm. Bypredetermining its pressure, the gas may be made to serve as a yieldablerelief medium which blocks entry of liquid from the line 23 to thechamber 44 under the forces required to center an uncoupled coupler, butpermits such entry under the greater deviational forces. As opposed tothe relief spring 42, the centering device employing the accumulators 43as its relief media, will of course require periodic checking to ensurenot only that the gas pressures in the chambers 44 are sufiicientbutalso that they are equal under normal conditions, a necessity to avoidbiasing of an uncoupled coupler away from center toward a side of lesserpressure.

In the third form shown in FIGUIE 5, the master and slave cylinder units19 and 20 at one side of the car are dispensed with and thesingle-acting units at the other side are replaced by double-actingmaster and slave units 45 and 46, respectively having theircorresponding sides connected by a pair of connecting lines or tubes 47.The double-acting master and slave units 45 and 46 have the pistons 22and 25 and connected piston rods 26 and 32 of a connected master unit 19and slave unit 20 of the first form. The difference in freecross-sectional area at opposite sides of the piston of each unit iscompensated for by connecting thecorresponding sides of the master andslave cylinders and using piston rods of such relative diameter in thetwo cylinders that the ratios of the free cross-sectional areas of therod and non-rod sides of the master cylinder to those of the connectedsides of the slave cylinder are the same. Deviational movements of acoupled coupler under special track conditions can be accommodated inthis double-acting unit form in either of the ways previously describedfor the single-acting unit form.

The automatic hydraulic centering device 18 is not a universal centeringdevice in the sense that a single set of specifications will apply toits installation on all cars. However, the specifications for a givencar are readily calculated. The factors involved in the calculations areindicated in FIGURE 6 in which the coupler 1 and bolster 16 are shown insolid line in the neutral or zero degree angling positions they wouldoccupy on straight track and in dot-and-dash line at maximum angling inthe positions they would occupy in centering the head of the coupler onunderlying track with the car on a curve of the minimum radius usuallyfound in subway trackage. The factors in determining the specificationsfor a particular car and the symbols designating them in the figure areas follows:

Maximum angle of bolster on minimum radius track 0 Maximum angle ofcoupler in centering head on minimum radius track 'y Coupler length fromface or coupling line 7 to pivot P for horizontal angling L Longitudinalspacing between coupler pivot P and truck pivot P L Moment arm of mastercylinder unit 19 or 45 L Distance of movement of arm L at angle 6 in adirection perpendicular to its central position L Moment arm of slavecylinder unit 20 or 46 L Distance of movement of arm L at angle 7 in adirection perpendicular to its neutral position L Internal freecross-sectional area of master cylinder 21 A Internal freecross-sectional area of slave cylinder Of the above factors, the angles0 and 'y, the coupler The above ratio being known for a given car andangles of less than 40, such as here involved, having substan tially theratio of their sines, the moment arms of the master and slave units andthe areas of their cylinders in suiting the centering device 18 to agiven car, are derived as follows:

Instead of being mounted on a car having a fixed underframe, as in theillustrated embodiment, the coupler with which the centering device 1-8is to be used, can be mounted in a floating sill of a cushion underframecar, an example of which is shown in my copending application Ser. No.475,975, filed July 30, 1965, now Patent No. 3,283,916. In such case itusually will be preferred to mount the or each slave cylinder unit 20 or46 in the floating sill rather than on the fixed underframe. This willrequire sufiicient flexibility in the liquid line or lines 47 or 23 toaccommodate the range of movement of the floating sill relative to thecar body but will not otherwise affect the centering unit or thecalculation of its specifications for a given installation.

From the above, detailed description it will be apparent that there hasbeen provided an improved automatic coupler centering device which canbe applied to any car having automatic couplers and, when so applied,will elfec tively center the head of an uncoupled coupler on underlyingtrack in position to couple with a mating coupler and, withoutdisengagement from the coupler, permit the deviational movements of acoupled coupler required to meet special track conditions. It should beunderstood that the described and disclosed embodiments are merelyexemplary of the invention and that all modifications are intended to beincluded that do not depart from the spirit of the invention.

Having described my invention, I claim:

1. In a railway car having a coupler swingable horizontally about apivot and a truck angleable horizontally about a pivot spaced rearwardlyfrom the coupler pivot, an automatic coupler centering device comprisingliquidconnected master and slave hydraulic means respectively connectedto said truck away from the truck pivot for response to horizontalangling thereof and acting on said coupler forwardly of the couplerpivot for centering a head of said coupler when uncoupled on underlyingtrack by horizontally swinging said coupler in response to saidhorizontal angling, and yieldable means disposed between said couplerand truck and operative When said coupler is coupled for enabling saidcoupled coupler to swing horizontally independently of horizontalangling of said truc 2. In a railway car according to claim 1 whereinthe centering device includes means connected to the coupler forwardlyof the pivot thereof and normally movable horizontally substantiallytherewith, and yieldable means for enabling said coupler when coupled toswing horizontally independently of horizontal angling of said truck,the slave means are connected to and act on the coupler through saidconnected means, and said yieldable means are in the connection of theslave means to said connected means.

3. In a railway car according to claim 2 wherein the yieldable means arerelief spring means acting between said connected means and said slavemeans.

4. In a railway car according to claim 2 wherein the yieldable means areaccumulator means in the liquid connection between said master and slavemeans.

*5. In a railway car according to claim 4 wherein the accumulator meansare maintained under a gaseous pressure sufficient to render theminoperative except when the coupler is coupled.

6. In a railway car according to claim 1 wherein the master and slavemeans are each cylinder means, and the master cylinder means arepivotally connected to both the body and the truck.

7. In a railway car according to claim 6 wherein the master and slavecylinder means are disposed respectively longitudinally and laterally ofthe car body.

8. In a railway car according to claim 7 wherein each slave cylindermeans has a cylinder fixed to a part of an underframe of the car bodyand a piston connected through the connected means to the coupler.

9. In a railway car according to claim 8 wherein the connected means isa yoke embracing sides of the coupler.

10. In a railway car according to claim 9 wherein the yoke has armsembracing the sides of the coupler, and the arms are lined withwear-resistant lubricious pads having arcuately convex faces confrontingthe coupler sides.

11. A coupler centering device for a coupler swingably mounted on aframe of a railway car having a wheeled truck traveling on track, saiddevice comprising fluid pressure responsive means disposed between saidcoupler and frame for swinging said coupler when uncoupled laterallyrelative to the longitudinal center line of said car, fluid motor means,means providing fluid communication between said fluid motor means andsaid fluid pressure responsive means, said fluid motor means beingdisposed between said truck and frame to sense the curvature of saidtrack as said truck turns thereon relative to said longitudinal centerline and to generate a fluid pressure change in said fluid motor meanswhich corresponds to the angular position of said truck relative to saidlongitudinal center line so that said fluid pressure responsive meansresponds thereto and swings said coupler when uncoupled to a position inwhich a head of said coupler is substantially centered with respect tothe underlying track, and yieldable means disposed between said couplerand truck and operative when said coupler is coupled for enabling saidcoupled coupler to swing laterally relative to said longitudinal centerline independently of said relative angular position of said truck.

References Cited UNITED STATES PATENTS 2,841,293 7/1958 Spencer 213-433,217,897 11/1965 Peterson 213-43 3,249,240 5/ 1966 Empson 213-433,255,891 6/1966 Cope 213-19 DRAYTON E. HOFFMAN, Primary Examiner US.01. X.R. 213 19, 2 0

